The last change was not the inductor, it was the board layout. Perhaps some new resistors, as you can see in the comparison-picture.
The Inductor was an earlyer change.
Hey, so i’m new here, my first post in fact. I’m just wondering if this driver board (KX70) has a user manual, spec sheet, or if there is any documentation or explanation anywhere as far as using it. I am hoping the driver has some user configurable settings, like modes, power levels, voltage output, and such. But I can’t find anything anywhere.
Does anyone know if this driver has a menu system? Does anyone know how it works? Does anyone have the manual or a web link?
I am looking for a driver to (re)mod an older 2S 18650 flashlight.
Now it runs with a 6V XHP50.2 and an FX-17A buck driver. But I want to have more modes and 100% output current stability through the entire battery discharge interval. And I hate the mode group change indication blinking of the FX17A in low mode.
So the big idea is to replace the 6V XHP50.2 to a 3V version, and install a higher output buck driver. P4000 would be an instant solution but the mode spacing sucks ( to me ).
Runs form 2s/3s and supplies 4800mA max - but it is a 6V output driver. My knowledge of DC-DC converters says that basically possible to drive a 3V led from a 6V driver since the current is controlled. Of course the output ripple, the overall efficiency, etc. can/will change. But there can be other restrictions or protection functions of the circuit I don’t know about.
What do You think? Do You have IRL experiences of such builds? Or maybe any experiences with this triver?
[ Of course I asked the seller. Of course said that apocalypse will occurs if I try it. )
You mean since the output voltage is precisely tuned to match the specified current flow, doesn't it?
Well, my answer is also yes, it should work well, but you may want to wait for some real electronics expert to chime in (just sent someone O:) a request).
I accidentally fitted a 3v XHP50.2 to a host with a 6v driver, I didnt even notice… it wasn’t till i went looking for the 3v emitter i realised my error… its still in there and it still works
Basically, but not exactly, yes.
I mean that LED drivers ( well, correctly built led drivers ) are controlled by/for output current ( through sense resistor ). Actual voltage is only a consequence.
But there can be some safety functions on output like overvoltage protection ( not important for buck drivers ) or LED fault protection ( undervoltage / shortcut protection - not important again for buck drivers ).
Or maybe the current sense resistor is a high side type and the feedback pin of the controller can only work on a higher voltage interval.
What ever they use in These I removed 2 of the 4 stack of resistors to drop the output down to about 4amps, changed the lens for one with a much shorter FL then mistakenly fitted the 3v 50.2
There are not many information available about the technical details of the lamp. :confounded:
Was there an old style toroid inductor driver in it, or a high frequency with a shielded SMD one?
Yeah, toroid drivers generally runs on low frequency resulting terrible flickering. I experienced that.
The 4.5A You linked is a 2 group driver, like the one I want to replace. This one has higher current, though. But in the lowest mode it always blinks 1 time as waiting for group change command. Annoying.
I think I will make a try with the Manta Ray driver. In the worst case I flushed 9 bucks. :partying_face:
And you're saying I removed 2 of the 4 stack of resistors to drop the output down to about 4amps, are you serious? Because if so, the driver must be a big buck driver. 8 amps in a 2S buck driver is nice, could you please share photos of it? No rush, of course, but take the oportunity to reset the sense resistors (lower it even further LoL), a 3V XHP50 can take that. And we will see if the driver can take the heat. ;-)
No need to feel ashamed or guilty for anything, its our creation so better learn from the experience.
I've taken a look at the video from the ad, looks like its long-necked so long stock focal lenght. Since you changed its lens now it must over-focus, doesn't it?
If the driver is good and the emitter is well heatsinked, it may be a good host after all.
Yes stock lens focus right at furthest point from emitter, with alternative lens prime focus is half way instead so a good 50% closer to emitter, but yes will over focus if you move it out to far, in all honesty with a genuine XHP50.2 fitted it puts out a reasonable amount of light
Heatsink is not great , the head is not connected to the body it slides forward/backward on the body so that large heatsink is basically just for show and does not aid cooling, the metal is quite thin even with current reduced to 4A it still heats up pretty fast
Perhaps 2k lumens is more truthful stock figure, the Fake XHP70’s do put out fair power
The driver has arrived.
I made a quick test just before feedback the order.
It works well with 3V XHP50.2, although the coil tends to whine softly in high and turbo. To be honest, it was just a really quick test, I used a cheap adjustable buck power supply with quite long wires and crocodile clip connections, and it seemed that better clamping decreases the buzz. So the final installation can be better in terms of noise.